Texas Instruments TI-83 Manual Book page 295

Equ4String(
expr(
inString(
converts to a string an equation that is stored
Equ4String(
to any
VARS Y.VARS
n (from to
Str Str1
which you want the equation to be stored as a string.
n
Equ4String(Y ,Str
converts the character string contained in string to
expr(
an expression and executes it. string can be a string or a
string variable.
string
expr( )
returns the character position in string of the first
inString(
character of substring. string can be a string or a string
variable. start is an optional character position at which to
start the search; the default is 1.
string substring[
inString( ,
Note: If string does not contain substring, or start is greater than the
inString(
length of string,
CATALOG
variable. n contains the equation.
Y
, or ) is the string variable to
Str9 Str0
n
)
start]
, )
0
returns .
, Strings, Hyperbolic Functions 15-7